Room security

Hi,
may I ask if there is a solution to the security room basis that the sensor goes 1/0 - 1 closed, 0 open?

Ummm... yes. But could you please provide a little more detail as to what you are doing and doing it with?

Well, as I say, I plan to secure a room. I have a microswitch on the door, which when closed door pass from 5V Arduino. I want to Arduino release of an alarm condition by pressing (I have 5).

And sorry for my english, i must use Google translator...

I have a microswitch on the door, which when closed door pass from 5V Arduino. I want to Arduino release of an alarm condition by pressing (I have 5).

Ok, you have a micro switch on the door, and if the door closes, then sound an alarm, or sound the alarm if the door is closed and open again?

Pressing what?